da Vinci® Pyeloplasty
The kidneys are two small fist-sized organs located behind the abdomen on each side of the spine. By producing urine, kidneys remove toxic by-products and excess fluids from the body to help maintain a critical balance of salt, potassium and acid.
Diseases of the kidney are found more often in racial and ethnic minority populations in the United States than in the Caucasian population. African Americans, Asian Americans, Hispanics/Latinos, and Pacific Islander Americans are three times more likely to suffer from kidney failure than Americans of European descent.
One of the most common conditions affecting the kidneys is urinary obstruction. Obstruction can occur anywhere in the urinary tract and when it occurs, medical attention is required. A urinary obstruction can create serious side effects like infections and kidney stones. If left untreated, blockages can cause chronic pain and may damage the kidney over time.
Blockage of the Ureter
The condition known as blockage of the ureter (tubes that transport urine from the kidneys to the bladder) is found in adults, but more commonly in children. Normally, a single ureter drains a single kidney but sometimes there may be two ureters draining one kidney. One ureter drains the upper part of the kidney and the second ureter drains the lower part. As long as they both enter the bladder normally, this "duplicated collecting system" is not a problem.
In rare cases, a child may be born with an ectopic (abnormally positioned) ureter. This is a ureter that fails to connect properly to the bladder and instead drains somewhere outside the bladder. In girls, the ectopic ureter usually drains into the urethra or even the vagina. In boys, it usually drains into the urethra near the prostate or into the genital duct system. The urethra is a canal that carries the urine from the bladder and in males also serves as a passageway for semen.
The most common cause of obstruction in the urinary tract in children is a congenital obstruction. This occurs at the point where the ureter joins the renal pelvis (called the ureteropelvic junction or UPJ). This is the area at the center of the kidney where urine collects and is funneled into the ureter. This type of obstruction occurs in roughly one in 1,500 children.1 These obstructions develop prenatally as the kidney is forming. Today, most cases are diagnosed on prenatal ultrasound screening.
In UPJ obstruction, the kidney produces urine at a rate that exceeds the amount of urine able to drain out of the renal pelvis into the ureter. This causes an accumulation of urine in the kidney. The accumulation, also called hydronephrosis is visible on ultrasound and often allows the doctor to predict the presence of UPJ obstruction before the baby is born.
Although less common in adults, UPJ obstruction can occur as a result of kidney stones, previous surgery or disorders that cause inflammation of the upper urinary tract.
- "Ectopic Ureter", American Urological Association Foundation, www.urologyhealth.org , URL: http://www.urologyhealth.org/urology/index.cfm?article=43&display=1